Dl4 Clipping Problem

I run an amp-less studio rig using a Damage Control Demonizer vacuum tube preamp pedal. My DL4 is at the end of the chain, so that any looping will contain my other effects pedals before the DL4. But I have noticed digital distortion/ clipping from the DL4's effects when using overdrive on the Demonizer. In other words distortion/ clipping when not looping, when using other DL4 effects like Reverse, when in high gain.

I've read in other forums where too hot of a signal coming from the effects loop send of an amp into the DL4 can overload the op amp and require repairs. Or just cause the distortion/ clipping. The other pedals before the DL4 are normal footpedals, and all (including the DL4) are clean-powered by a Voodoo Lab PS-2, so would the issue be with the Demonizer preamp? It has a Nominal Output Impedance of 100 ohms, and a Maximum Output Signal Level of 0 dBv.

Is this an acceptable output level coming into the DL4? Could a factory reset (holding A&tap on power up; holding A&C on power up) clear it up?